The intestinal flora of man and animals, in particular warm-blooded animals, contains numerous species of micro-organisms. In particular, these are bacteria the presence of which is essential, not only to digestion, but also, and more generally speaking, to health.
Therefore, numerous food products or drugs have been developed with a view to providing micro-organisms capable of reconstituting the intestinal flora of man and animals.
In manufacturing such food products or such drugs, the micro-organisms are generally dehydrated in advance. They are further associated with compounds, said compounds advantageously having prebiotic properties, i.e., being capable of stimulating the growth of micro-organisms.
However, the dehydrated micro-organisms of these food products are subjected to stresses. Furthermore, these are stresses which are not necessarily due to the environment. Chemical stresses such as acidity, or enzymatic stresses may be cited, for example.
The effect of these stresses is to affect the viability of the dehydrated micro-organisms with the result being that, for all practical purposes, it is not possible to guarantee the presence of a substantial quantity of revivable micro-organisms in these food products, and this is so even when the storage life of said products is short.
Of course, it has been sought to develop compositions containing revivable dehydrated micro-organisms in which said micro-organisms are protected from the physicochemical stresses to which they are normally subjected.
These compositions aim to protect the micro-organisms by coating them with a protective substance. They are disclosed, in particular, in the documents published under the numbers FR 2 806 417, FR 2 748 752 and US 2004/0175389. In the document FR 2 806 417, micro-organisms are coated with a protective hydrophobic substance. In addition, in the patent FR 2 748 452, bacteria are coated with polymers. Finally, in the document US 2004/0175389, bacteria are coated with an alginic acid gel.
Nevertheless, the coating of dehydrated bacteria is an operation which is stressful in itself, and which consequently ends up destroying a substantial quantity of the bacteria present in the compositions obtained. Furthermore, coating is a relatively complex and random operation from product to product.